Power Doppler ultrasound in musculoskeletal disease: a systematic review

OBJECTIVE: To evaluate the performance characteristics of power Doppler ultrasound as a diagnostic and monitoring tool in the assessment of musculoskeletal disease through a systematic review of the literature. METHODS: Search Strategy: We performed a literature search of PUBMED (1966 to June 2005). Selection Criteria: Only original research reports written in English involving musculoskeletal disease and power Doppler ultrasound were included. Reviews were noted but not included. Data Extraction/Reporting: The design, subjects, methods, imaging protocols, and performance characteristics studied in the research papers were reported. RESULTS: Of 3568 identified reports, 139 involved power Doppler ultrasound of the musculoskeletal system. Fifty-three of these reports met the inclusion criteria. Ultrasound machine settings were specified in 63% of reports. Rheumatoid arthritis was the most commonly studied musculoskeletal disease (64% of papers). Validity was the most studied performance characteristic (94% of reports), while reliability and responsiveness were studied in 17 and 34%, respectively. CONCLUSIONS: Although the majority of research reports of power Doppler ultrasound assessment of the musculoskeletal system evaluated validity, less than half reported reliability and responsiveness. Further work is needed to evaluate power Doppler ultrasound assessment of the musculoskeletal system before it can be used to guide clinical decisions or be used as an endpoint in clinical trials.